


Cat-Earred Catastrophe

by GilgaNyan (NarryEm)



Series: Adventures in Chaldea [9]
Category: Fate/Grand Order, Fate/stay night & Related Fandoms
Genre: Alternate Universe - Canon Divergence, Animal Traits, Cat Ears, Fluff, M/M, Smut
Language: English
Status: In-Progress
Published: 2018-10-21
Updated: 2018-10-21
Packaged: 2019-07-01 11:07:14
Rating: Mature
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 3,562
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/15772872
Author URL: https://archiveofourown.org/users/NarryEm/pseuds/GilgaNyan
Summary: Da Vinci said that it was an error in the summoning system.  Dr. Roman said that it was a fluke in the mana flow.  Whatever the hell it was, at the end of the day, Ritsuka could not do anything about the fact that he had cat ears on his head, along with the Servants in Chaldea.





	Cat-Earred Catastrophe

**Author's Note:**

> I dunno where this came from. I was reading a doujinshi where Gilgamesh is a cat and well . . . yeah. who doesn't like a good ol' nekomimi?

 

 

Ritsuka wakes to a cacophony of animal sounds outside his door.  Thinking that he is still dreaming, he turns over in his bed and covers his ear with a pillow.

“Senpai!” Mash shouts, bursting through the door.  Her outcry is followed by several crashing sounds.  The young Master sighs, counting to ten before he emerges from his blanket cocoon.

He rubs his eyes once.  And twice.  Nope, his eyes are not playing tricks on him.  Everyone in the room have mysteriously sprouted animal ears.

He has to admit that Mash looks adorable with tanuki ears on top of her head.  The Servants, who look just as frazzled as Mash and some even furious, have various animal ears on their heads as well.  Arthur has what appeared to be brown bear ears, Gawain a set of wolf ears, and Karna had lynx ears, and so on for the Servants who have barged into the mage’s bedroom. 

“Uhm . . .  what the hell is going on?” Ritsuka asks, not expecting an answer back.

“It’s simple, really,” Da Vinci says, seemingly appearing out of thin air.  She had reddish brown fox ears and a matching tail, a feature that Tamamo does not seem to appreciate.  She must think that Da Vinci is her rival or something in terms of charms.

“There has been an error in the summoning system.  Nothing serious.  It looks like the coding mistakes resulted in small tweaking of the Heroic Spirits’ Origins, hence the animal features that have been added to their appearance.”

“What Da Vinci is saying is,” Roman intercepts, “this should be a temporary inconvenience.  In addition to the animal ears and tails, some Servants have developed animal behaviours as well.”

“Did not!” Gawain protests.  The small whimper and bit-off howl contradicts his statement, though.

“We should accept the situation as it is,” Caster Gilgamesh concludes.  In the midst of the chaos, Ritsuka has somehow missed the Caster’s entrance.  He looks as striking as ever, literally taking Ritsuka’s breath away with the sheer force of his otherworldly beauty.  The pale gold cat ears perched atop his golden hair fits his cool, aloof personality, Ritsuka thinks.

“Has no one told you that staring at a King like a fool is rude?” Gilgamesh admonishes, albeit with fondness dripping from his voice.  Oh, right.  This exquisite creature somehow returns Ritsuka’s love and affection for him.  It’s too easy to wake up and forget about that fact since there is no way that a mere human boy like him can hold the King of Heroes’ intrigue.

“Please fix this as soon as possible,” Emiya grouches.  He has sprouted a set of shiba-inu ears and that really suits him.  His tail twitches behind him as if in irritation.

Gilgamesh wrinkles his nose.  “Something—or rather, _someone_ —smells like a wet dog.  It seems that my senses have been heightened to that of a cat.  How bothersome.”

“Y-you shouldn’t go around telling people that they smell like wet dogs, King Gilgamesh,” Ritsuka whispers.  He can feel the murderous aura emanating from the red Archer.

“It’s not limited to him, dearest Ritsuka.  The whole lot of you smell like the pungent earth that has been soaked with days’ worth of rain.  This is going to take some time to get used to.  I think I’ll go back to my room.”

His lingering touch on Ritsuka’s elbow down to his wrist cannot be read as anything other than an invitation for later.  Ritsuka will have to take up on that as soon as the Servants clear out of his room.

“Senpai.  What’s your opinion on this?” Mash asks.

“I guess all that we can do is to wait this out.”

“This had better not last too long.  At this rate, our enemies will laugh themselves to death.”

Ritsuka can’t argue with him there.  As cute and handsome as the heroes look, to an outsider their appearances may be worthy of a good laugh or two.

 

 

 

~

 

 

 

“Ritsuka~  You sure took your sweet time coming here,” Gilgamesh purrs (literally), pouting.

The King has chosen to rid himself of his usual in favour of a gossamer silk kimono in the colour of pale gold and cherry blossom pink.  Since he has a habit of skipping underwear, Ritsuka has a full view of the King’s flawless body.  He has to focus on looking directly into the King’s scarlet eyes so that his lower body won’t get any funny ideas too quick.

“So-sorry.  Shuten and Tamamo took _their_ sweet time to leave,” Ritsuka explains.

“And what shall you do to be granted forgiveness from me, Ritsuka?”

The mage blushes bright red from his face down to his neck.  “Ah-I, uhm, I think I have a few ideas.”

The King of Uruk chuckles at how the young boy’s voice squeaks at the end.  “Sometimes I still wonder if the feelings you harbour for me are mere side-effects of my accursed charisma.  No matter.  Given enough time, even a curse can turn into true love.”

“I-is that so?” Ritsuka stutters.

Gilgamesh locks his fingers behind Ritsuka’s nape, pulling him in for a light, chaste kiss on the corner of his lips.

“I’ve seen that kind of story unfold countless times.  It’s a love story, a tragedy, or perhaps not a story to begin with.”

Ritsuka isn’t sure if he follows but he nods nonetheless.  The confusion must have shown on his face for the King laughs and pats Ritsuka on the head.

“You must think me arrogant for speaking of love when I myself have not experienced it for myself for millennia.  True, I have only ever loved two people in my life: my one friend Enkidu and my current Master.  You needn’t worry your pretty little head over the small details.  In years to come, you’ll learn that not everything that felt big at the time leave a sizable impact in the course of your whole life.”

With that, Gilgamesh kisses Ritsuka once more, this time right on the centre of his lips and teases them apart.   Ritsuka is always helpless when it comes to Gilgamesh, especially in bed.  It cannot be helped that he had no sexual experience beyond the bounds of the internet before meeting the Heroic Spirit.  Granted, Gilgamesh is an amazing and eager teacher but every now and then, Ritsuka feels pangs of jealousy for those who were held in Gilgamesh’s arms before him.

And every now and then, when Gilgamesh can sense that Ritsuka is having those moments of self-doubt and inferiority, he whispers these words: ‘Rejoice, Ritsuka, for you shall be the last person to be held in my arms.  My love for you is genuine and cannot be tainted by the flow of time.  Our time together is finite but the moments we spend together in intimacy shall be infinite in our memories and hearts.”

There is no way that Ritsuka can come up with a follow-up to Gilgamesh’s beautiful and heartfelt words.

“You always know the best thing to say and that’s not fair at all.”  It is now Ritsuka’s turn to pout.

“Humans got to where they are now because they never ceased to explore and to learn.  You are still young, my adorable little Master.  You’ve plenty of time to catch up to me.”

Ritsuka has half a mind to point out that they may not have that long of a time together—there is no way of knowing how long the staff a Chaldea can keep the facility operative once the crises have been resolved—but there is something in Gilgamesh’s blood-red eyes that keeps that thought to himself.

“I suppose so, yeah,” Ritsuka sighs.

“Sighing is for those who worry about the little nothings,” Gilgamesh murmurs.  His lithe fingers combing through Ritsuka’s hair in a soothing rhythm.  The cold touch of his golden gauntlet is refreshing in a way.  “And for those with an actual brain.”

“Hey,” Ritsuka complains.  His witty comeback is lost in his throat at the sight of his laughing King.  It truly is not fair at all that a man as beautiful as Gilgamesh can exist.

“I jest.  You have grown into quite the little strategist, Ritsuka.”  His cat tail swings behind him lazily, the tip curling every few seconds.  His lively tail belies the calm, collected tone of his voice.

Completely on impulse, Ritsuka reaches behind Gilgamesh to stroke the end of his tail.  The King lets out a loud _mrrow_ , at which both Ritsuka and Gilgamesh himself startle.  The way that the Caster claps a hand over his mouth is too cute for words.

“Did that feel good, my King?” Ritsuka asks, an idea forming in the back of his head.

“No,” Gilgamesh answers too quickly.  He is also avoiding Ritsuka’s eyes.  He withdraws his tail to himself, wrapping it tightly about his hips.  “I simply was not expecting for you to touch it, is all.”

“Heh~”

Ritsuka jumps on top of Gilgamesh and pins him down to his (unnecessarily ginormous and extravagant) bed.  Gilgamesh glares up at the Master when he ends up with his hands held captive above his head.  His golden headdress and earrings create loud jangling sounds as they jostle about, fighting for the top in the literal sense.

Gilgamesh rolls his eyes as he lets Ritsuka roll him to his back.  Ritsuka lies down with his body flush to Gilgamesh.  His hands roam up and down Gilgamesh’s body for a minute or two before they settle on the Servant’s head.

“I suppose you want to test out the sensitivity of my ears as well,” Gilgamesh says dryly.  His tail tickles Ritsuka in the stomach as it flaps in annoyance.  “Go ahead.  I shall allow it for today.”

“Thanks.” Ritsuka kisses the King on the tip of his nose.

Gilgamesh’s is hair is fine and soft, softer than anything Ritsuka as touched in his life.  The hairs on his newly acquired cat ears have the same softness.  The cat ears flatten against Gilgamesh’s skull upon the first touch.  At the same time, another loud feline sound erupts from the King.

Ritsuka grins.  “Are you still going to insist that this was from surprise?” 

He scratches the backs of the ears, earning himself a drawn-out purr from Gilgamesh. 

“Alright, _mongrel_.  I shall admit that it does feel somewhat pleasant.  It appears that the mix-up of the summoning system and alteration of my Spirit Origin resulted in my obtaining catlike traits.”

As if reading Ritsuka’s next set of actions, Gilgamesh removes himself from the bed.  In the blink of an eyes, Ritsuka finds Gilgamesh stood at the foot of his bed dressed in a navy button-up shirt and dark grey trousers.

“We are _not_ going to do that,” Gilgamesh hisses.  For a split second, his pupils narrow into slits before dilating to human likeness.

“But we won’t get another chance like this.  Your Majesty!” Ritsuka begs.

“A no is a no, Ritsuka.  Consent is an essential part of sex and I shall not permit you to play with these.” Gilgamesh’s ears and tail move to emphasise his words.

“You’re being awfully stingy,” Ritsuka complains.  He flings himself onto the mattress with his limbs spread out.

“Grow a pair of overly sensitive appendages yourself and you’ll see why I’m acting this way,” Gilgamesh counters.

“Am I allowed to at least kiss you?” Ritsuka asks, hoping that he doesn’t sound as desperate as he feels.

The way Gilgamesh tilts his head to the side is decidedly catlike, particularly when coupled with his perked ears and swishing tail.

“That much I can tolerate,” Gilgamesh allows.  “But be warned that punishment will follow should you try to test my patience.”

Ritsuka gulps.  For some reason, he is not wholly opposed to that.

Maybe he’ll find out for himself how the ancient King punishes his lovers before lunchtime today.

 

 

 

~

 

 

 

“Incompetent imbeciles!”

Gilgamesh smashes his fist against the wall.  Some of the mongrels scurry away lest they end up on the receiving end of the King’s anger.  Those mongrels had the gull to tell him that they had no concrete estimates as to how long it will take them to fix the summoning system.

Which meant that Gilgamesh, the one true King of Kings and oldest of the heroes, was stuck with these cat ears for the time being.

He pokes at the strange new set of ears.  They feel like his own ears, reacting to the touch.  It doesn’t feel pleasant nor unpleasant to touch them.  It’s a good thing that he did not grow a tail like his pathetic, weak Caster self.

If it seems like he is stomping around to make his wondrous golden armour clang and clash louder than the usual, it is entirely a coincidence.  He has to resist the urge to drive his fist through a wall like a kid throwing a temper tantrum.  A King does not throw temper tantrums, his reminds himself.  He unleashes his fury at one hundred percent to those who cross him.

“Whoa, sorry there, m—oh, it’s you again,” an unimpressed voice mutters.

Gilgamesh lifts up his crimson eyes only to stare into cool green ones. 

“We have got to stop meeting like this, holy sword wielder,” Gilgamesh purrs.  Damn.   It was not in his intention to literally purr but the insipid cat ears somehow resulted in a creation of the vibration in his chest as he spoke his words.

“Quit calling me that,” Arthur Pendragon snaps.  “You always called me that as you taunted me in Tokyo.”

Gilgamesh has to peer into that world’s timeline for a brief moment to grasp the full situation.  “Ah, yes.  Is it not true though, King of Knights?  You are the wielder of the most famous holy sword in all of human history and legends combined.  Should you not take pride in the fact that your name is recognised in virtually every corner of the civilised world?”

Arthur narrows his eyes.  Gilgamesh detects the tightening of his tender, soft rose-hued lips.  His lips tasted as sweet and rough as they appeared.  The King of Uruk would not mind having a taste of those if the opportunity presented itself.

Such opportune moment is right now, it would seem.

The righteous knight is obviously flattered, his pale face mottled red to the tips of his ears.  Gilgamesh strides forwards and presses his lips over a pair of unassuming lips.  Arthur breathes in sharply, attempting to take a step back.  Gilgamesh prevents that with a firm hand planted on Arthur’s back.  His other wanders off to rest in Arthur’s soft, pale blonde hair.

“What in the Devil’s name do you think you are doing?” Arthur asks, breathless, when Gilgamesh releases him from the kiss.

“Kissing you. I’ve taken a liking to the taste of your mouth, as evidenced by my actions,” Gilgamesh answers simply.

Arthur’s face is now a bright flaming red.  It would be swell if Gilgamesh had one of those devices to capture the knight’s flustered face and save it.

“You can’t go around kissing people whenever you feel like it!”

“Actually, I can.  It is in the King’s rights to do as he wishes for he is not bound by the ideals of right and wrong.  I am the law, after all.”

The Brit frowns.  “I feel like this is not the first time that I’ve heard you utter those words.”

“Perhaps.  I do rather enjoy the reactions I get from you.  You’re expressive only in the way that an innocent child can be in some ways Arthur Pendragon.”

“I-I am not an innocent child!  I’ve fought in battles and led ferocious battles!” Arthur denies.

“The type of innocence I am referring to is of the heart of hearts.  You chose to become Britain’s King for the people.  You had no ambitions nor desires as King.  You only served when in fact the people of your nation should be serving _you_.”

“Do not speak as if you know me better than I know myself, King of Heroes.  You do not have the rights to pass judgment on what makes a good King.  A tyrant such as yourself has no place in such discussion.”

“Is that so?” Gilgamesh arches an eyebrow.  “A King must be prepared to rule in tyranny if his interests lie in tandem with what is best for the people.  You needn’t burden yourself with what is right and wrong if the means serve to deliver the end you desire.”

“Do not presume to know who I am, Archer.  To me you are nothing but an arrogant man who think he owns the world.”

Gilgamesh laughs, at which Arthur frowns deeply.  “Foolish mongrel.  I do _own_ the world.  This world is forevermore my garden.  All creatures that inhabit it are no more than playthings that may serve to amuse me.”

His eyes follow the movement of Arthur’s hand as it jerks towards the hilt of his sword.

“You do not have the gall to draw forth that sword.  Your chivalry condemns you so.  The knight in you prevents you from inflicting harm to the civilians who also inhabit this tiny fortress.”

“On the other hand, you wouldn’t think twice before you let a few Noble Phantasms fly out of Gate of Babylon,” someone points out dryly.

“Faker.”

The Japanese man steps in between the two kings.  “Can you go anywhere without invoking anger and hatred, O King of Heroes?” he mocks.

Gilgamesh scoffs.  “A King need not concern himself with what those beneath him think of him.  A faker who can only conjure up imitations of the weapons housed in my vast treasury and carries the borrowed ideals of a foolish father is further below the commoners.”

“Careful, Gilgamesh.  I can tolerate insults to my person but you will not insult Kiritsugu or his ideals,” Emiya growls.  A feral literal growl erupts from his throat.

“Have you been betrayed by the humans so much that you’ve become a rabid dog now?” Gilgamesh taunts.

“Do me a favour and shut up,” Arthur interjects.  He turns on his heel and leaves.  The faker of a Servant follows suit.

“Until we meet again, King of Knights,” Gilgamesh calls out.

 

 

 

~

 

 

 

Emiya keeps stealing glances of the legendary Arthur Pendragon next to him.  He is so different from the Altria he knows from his own world, who was a girl contrary to the legends that depicted the stories of King Arthur’s rise and fall.

“Emiya, was it?” Arthur says, breaking Emiya’s internal musing.

“Yes.  Hello to you as well, King Arthur,” he says curtly.

Saber grins.  “Just Arthur will do.  You aren’t one of my knights, after all.  I hear that you’ve been with Master and Mash for quite some time.  Any tips for surviving in Chaldea?”

Emiya shrugs.  “I simply carry out my duties as a Servant, that is all.  I think that you’ll be fine as long as you don’t get into another fight with Goldie over there.”

“You’re right,” Arthur admits with a hearty chuckle.  “Something about that bastard makes my hackles rise, so to speak.  I imagine that I’m not the only one who feels that way, though.”

The Archer shrugs again.  “We may have had bad blood in a past Grail War held in a different world from ours but that doesn’t concern me.  He is but a selfish, cocky king.”

Arthur raises one eyebrow.  “I could very well fit into that description, y’know.”

“Yes.  You could.  But you don’t.  You sacrificed too much of yourself for the sake of your country.  On the other hand, you could have afforded to have been a more selfish, arrogant king.  A king without any ambitions and desires is but a husk of a leader.”

“That’s cut me deep, Emiya,” Arthur says, a hand spread over his own chest.  But the playful look in his eyes indicates that he isn’t all that bothered by Emiya’s words. 

“Tell me, Arthur.  What would you ask of the Grail if you had the chance?” Emiya blurts out.

“Me?  Uhm, I don’t know.  I think I’ll decide in the moment,” Arthur answers.  He doesn’t appear to be lying.

“Is that so.  I guess that differentiates you from the King Arthur I knew.  Altria wanted to change the past so that someone else could have had the chance to become the King of Britain.  She didn’t want the burden of being king.”

Arthur looks genuinely shocked.  “She did?  I wonder why. . .”

“Perhaps the burden of protecting a country and leading it was too big a burden for a little girl’s shoulders to bear.  After all, your era was not kind to women.  She pretended to be man even to the majority of the Knights of the Round Table, is what I know.”

“’Tis all true.  It was hard enough trying to be the righteous king as I was so I cannot even begin to imagine the struggles the other me must have faced.”

Silence hangs heavy between them as they continue to walk down the hallway.  Emiya did not know that their rooms were situated close together until now . . .

“I’m, uh, gonna go see if there’s something I can eat in the canteen,” Arthur says.  “Bye, Emiya.  Have a nice day.”

“You, too, Arthur,” Emiya replies out of reflex.  Perhaps there are more similarities between the two King Arthurs.  The thought brings a hesitant smile to his lips.

**Author's Note:**

> lots of kinky smut to come in part two . . . stay tuned!


End file.
